While the terms "eating disorders" and "disordered eating" are often used interchangeably and the differences between the two are often subtle, they are different problems. Both are prevalent in adolescence and young adulthood, but they have been reported in children and older adults, too. Whoever they affect, one thing is for sure: both can have harmful consequences. Disordered eating can lead to eating disorders.

Eating Disorders

An eating disorder may begin when someone starts to eat either smaller or larger amounts of food than they usually do, but at some point the compulsion to eat less, or more, spirals out of control. The person often becomes overly preoccupied with eating, food, and weight control, sometimes to the point that they cannot concentrate or focus on other things in life. People with eating disorders often have other mental illnesses such as depression, substance abuse, or anxiety disorders.

Over time, a person with anorexia nervosa may experience a loss of bone density, dry hair and skin, hair loss, the growth of a downy layer of hair all over the body, muscle loss and weakness, and an abnormally slow heart rate and low blood pressure.

Despite all the research that has been conducted to gain an understanding of eating disorders, the cause of eating disorders, whether it be biological, behavioral, or social, is unclear. Concerns about weight and body size and shape play a role in all eating disorders, but the actual cause may include cultural and family pressures, emotional disorders, genetics, and biological factors.

Statistics from the National Institute of Mental Health suggest that 2.7 percent of adolescents suffer from an eating disorder and that girls are more than two and a half times as likely as boys to have an eating disorder. According to the American Academy of Pediatrics, eating disorders are on the rise, particularly in children under the age of 12 years, males, and minority populations. Five to ten percent of all cases of eating disorders occur in boys.

There is a wide range of abnormal eating behaviors, but there are only three clinically identified eating disorders according to the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-IV): anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified (EDNOS). The third category was designed to describe behaviors that meet some but not all of the criteria for anorexia or bulimia.

Anorexia Nervosa
Anorexia nervosa is a condition that goes beyond out-of-control dieting. It is estimated that .6% of the United States adult population and .5% of adolescent girls have anorexia nervosa.

Anorexia nervosa is characterized by:

  • Emaciation
  • A relentless pursuit of thinness and unwillingness to maintain a normal or healthy weight
  • Intense fear of gaining weight
  • Distorted body image, a self-esteem that is heavily influenced by perceptions of body weight and shape, or a denial of the seriousness of low body weight
  • Lack of menstruation among girls and women
  • Extremely restricted eating.

Many people with anorexia see themselves as overweight, even when they are clearly starved and malnourished. They may weight themselves frequently, portion their food carefully, and eat tiny quantities of only certain foods. Often they will wear baggy clothes to hide their body. Sometimes people with anorexia nervosa also engage in a cycle of binge-eating followed by extreme dieting or purging behaviors such as vomiting, excessive exercise, and/or the misuse of enemas, diuretics, or laxatives.

Over time, a person with anorexia nervosa may experience a loss of bone density, dry hair and skin, hair loss, the growth of a downy layer of hair all over the body, muscle loss and weakness, and an abnormally slow heart rate and low blood pressure. Eventually, the heart and brain are damaged from malnutrition.

Of all the types and subtypes of eating disorders, anorexia nervosa is the deadliest. In a recent meta-analysis, the mortality rate for those with anorexia nervosa had a weighted annual rate of five deaths per 1000 person-years. Of those who died, one in five died of suicide.

Bulimia Nervosa
Bulimia nervosa is characterized by episodes of excessive eating followed by some form of purging, such as self-induced vomiting, abuse of laxatives or diuretics, or excessive exercise, as a form of weight control. Bulimia often includes periods of anorexia. People with bulimia nervosa are usually at a healthy or normal weight though some may be slightly overweight. Since bulimic behavior is often accompanied by feelings of disgust and shame, it is usually secretive. A person with bulimia nervosa may purge anywhere from several times a day to several times a week.

The prevalence of bulimia is estimated at .6% of the US adult population. Between 1% and 2% of adolescent girls in the United States meet the criteria for bulimia nervosa.

Common signs and symptoms include:

  • Bruised or callused knuckles, bloodshot eyes, light bruising under eyes
  • Sore throat and/or swollen glands
  • Binging and/or purging
  • Fear of not being able to control eating
  • Trips to the bathroom following meals, sometimes using running water to hide the sound of vomiting.
  • People with bulimia nervosa experience worn tooth enamel, and sensitive and decaying teeth as a result of exposure to stomach acid. Gastrointestinal problems such as acid reflux and intestinal irritation are common. Continuous purging of fluids can lead to severe dehydration and electrolyte imbalances which can ultimately lead to a heart attack.

    Eating Disorders Not Otherwise Specified
    Eating disorders not otherwise specified (EDNOS) includes abnormal eating behaviors that do not meet the criteria for diagnosis as either anorexia or bulimia nervosa, but are clinically significant. Though it is uncertain how many people fall into this category, the prevalence of EDNOS is estimated to be somewhere between .8% and 14%, depending on what definition and criteria are used. EDNOS is the most common diagnosis among people who seek treatment for eating disorders.

    Binge-eating disorder is one type of EDNOS. A person with this disorder loses control over his or her eating, but unlike bulimia nervosa, episodes of bingeing are not followed by any type of purging activity. People with binge-eating disorder are usually overweight or obese, putting them at greater risk for chronic weight-related illnesses. In addition, they experience guilt, shame, and distress about their behavior, and this often leads to more binge-eating behavior.

    Disordered Eating

    Disordered eating is characterized by a wide range of unhealthy eating behaviors and weight loss methods such as chronic restrained eating, compulsive eating, and habitual dieting. It may also include irregular eating patterns, avoidance of certain foods or food groups, and the denial of physical hunger and satiety, usually for the sake of losing weight. Disordered eating may begin as an effort to drop a few pounds or get in better shape, but the behaviors can become obsessive. Some disordered eating patterns can include symptoms of both anorexia and bulimia nervosa.

    Disordered eating may begin as an effort to drop a few pounds or get in better shape, but the behaviors can become obsessive… It is important for such eating habits to be identified and changed before they become severe and develop into an eating disorder.

    While not as serious as clinically diagnosed eating disorders, disordered eating still has a negative effect on a person's emotional, social, and physical health. Disordered eating can affect a person's daily life when their thoughts about food, weight, and body size lead to stringent eating and exercise practices. The person may feel tired and depressed and have difficulty with mental functioning and concentration. Malnutrition is a possibility, and bone health can be compromised. When present in children or adolescents, physical growth and brain development may be affected.

    In a study published in the July 2011 issue of the Journal of the American Dietetic Association of over 2,000 young people, researchers at the University of Minnesota examined whether adolescents who diet and engage in disordered eating behaviors continue these behaviors into young adulthood. The behaviors that were studied included dieting, unhealthy weight control behaviors (fasting, eating very little food, using a food substitute, skipping meals, or smoking more cigarettes), extreme weight control behaviors (diet pills, vomiting, laxative or diuretic use), and binge eating with loss of control. The researchers concluded that many of these behaviors continue through young adulthood, and that adolescents who begin such behaviors increase the risk that they will continue these behaviors 10 years later.

    While disordered eating is not as consequential as an eating disorder, it can lead to one so it is still serious. It is important for such eating habits to be identified and changed before they become severe and develop into an eating disorder. Regardless of whether an individual has a clinically diagnosed eating disorder or exhibits patterns of disordered eating, the behaviors associated with each are harmful to health and intervention by a health professional is needed.